Study on the crystallization process of GaSb-Sb2Te3 pseudobinary films for phase-change random access memory.
Study on the crystallization process of GaSb-Sb2Te3 pseudobinary films for phase-change random access memory.
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DOI：
10.1166/jnn.2013.6057
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发表时间：
2013-02
影响因子：
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通讯作者：
Yegang Lu;Simian Li;Sannian Song;Zhitang Song;Bo Liu;T. Wen;T. Lai
中科院分区：
文献类型：
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作者：
Yegang Lu;Simian Li;Sannian Song;Zhitang Song;Bo Liu;T. Wen;T. Lai
用非等温电阻法研究了用GaSb和Sb2Te3靶共溅射制备的GaSb-Sb2Te3准二元膜的晶化过程。通过现场电阻-温度测量直接确定了结晶参数。由基辛格曲线推算出结晶活化能和速率因子。用Ozawa方法计算了动力学指数。晶化温度(185-228℃)和活化能(2.01-5.65 eV)随Ga浓度从5%增加到34%而单调增加，平均动力学指数从1.63下降到1.02。在平均动力学指数小于1.5的情况下，当Ga含量大于10mol%时，其晶化机制为从晶核一维生长。用Johnson-Mehl-Avrami方程从理论上估算了所研究组份的晶化时间，并用激光脉冲引起的反射率变化进行了实验测量。结果表明，Ga27Sb47Te26薄膜的晶化时间最短，是一种潜在的相变随机存储器应用材料。
Non-isothermal change in electrical resistance was used to investigate the crystallization process of GaSb-Sb2Te3 pseudobinary films prepared by co-sputtering using GaSb and Sb2Te3 targets. The crystallization parameters were determined directly by in-situ electrical resistance-temperature measurements. The activation energy of crystallization and rate factor were deduced from the Kissinger's plot. The kinetics exponent was calculated using the Ozawa's method. The crystallization temperature (185-228 degrees C) and activation energy (2.01-5.65 eV) increased monotonically with increasing Ga concentration from 5 to 34 mol%, while the average kinetics exponent decreased from 1.63 to 1.02. The crystallization mechanism of the compositions with Ga concentration more than 10 mol% was one-dimensional growth from the nuclei due to the average kinetics exponent smaller than 1.5. Crystallization time of the studied compositions was estimated theoretically by the Johnson-Mehl-Avrami equation and measured experimentally by the reflectivity change induced by the laser pulse. It is shown that Ga27Sb47Te26 film exhibited the shortest crystallization time, suggesting a potential candidate for phase-change random access memory application.